Low profile vacuum toilet

ABSTRACT

A vacuum assist toilet provides an efficient flushing in a tank of relatively low height. A container assembly (36) includes a largely sealed container (34) that lies within the tank (12) to hold water that is dispensed in a flushing so as to create a vacuum at the top of the tank for application to the toilet bowl outlet. The flush valve (40) lies within the container, and the lower portion of the container is isolated from tank water surrounding the container, so water used during a flushing is obtained primarily by the outflow of water within the container and through a valve seat at the bottom of the container. A baffle (130) largely surrounds the region containing the flush valve, to produce an earlier dosing of the flush valve.

This is a division of Ser. No. 09/001,640 filed Dec. 31, 1997, U.S. Pat.No. 5,926,860.

BACKGROUND OF THE INVENTION

U.S. Pat. No. 5,142,712 describes a modern vacuum assisted toiletwherein a vacuum created during a flushing, is coupled to the toiletbowl outlet to draw out the contents of the toilet bowl while waterdumped into the toilet bowl pushes out the contents. The vacuum iscreated by placing a largely sealed container within the conventionaltoilet tank and allowing the water level in the container to drop aswater is flushed from the tank, with the dropping water level creating avacuum in the upper portion of the tank. Such vacuum assisted toiletsallow the use of less water, as where it is decreased from 31/2 gallonsto 1.6 gallons, while retaining a large diameter toilet outlet such asmore than 21/8 inch, and while efficiently removing the contents of thetoilet bowl.

There is a demand for low profile vacuum assist toilets, wherein thetoilet tank extends a minimum height above the level of the top or rimof the toilet bowl. Where the tank is tall, such as more than fourteeninches above the top of the toilet bowl, it dispenses water with a largehead, or pressure, and the water rapidly fills the bowl to efficientlyflush it. If such an efficient flushing could be obtained using a tankof lower height, this would create a toilet of more attractiveappearance.

SUMMARY OF THE INVENTION

In accordance with one embodiment of the present invention, a vacuumassisted toilet is provided, which creates an efficient flushing in atoilet of only moderate height. The toilet includes a largely sealedcontainer which creates a vacuum when the water level in it drops, and aflush valve that lies within the confines of the container so water canflow rapidly out through the flush valve to the toilet bowl. At leastthe bottom half of the container is isolated from the surroundings toprevent the free flow of water between the bottom portion of thecontainer and the surroundings during a flushing.

The container includes top, bottom, and side walls that are primarilysealed from the surroundings. However, the bottom wall includes a valveseat opening through which water flows towards the toilet bowl during aflushing, a water conduit for refilling the tank, and a hole throughwhich the vacuum conduit extends. When the container lies in a tank, aninlet valve that lies in the uncontained region outside the container,flows water into the tank at each flushing to refill the tank to apredetermined high water level. The outer end of the water conduit whichopens to the tank, lies a small distance below the high water level.This refills the container while assuring that little water flows fromthe tank to the container during a flushing, and even that water has alarge head. Instead, almost all water used in a flushing flows directlyfrom inside the container through the flush valve seat, for rapid wateroutflow.

A barrier lies in the container around the flush valve and ts valve seatThe barrier causes most outflow in a primarily downward directionthrough the valve seat, and also closes the flush valve member early toprovide a large head (water pressure) during almost the entire flushingwhen water is flowed out of the container.

The flush valve member is pivotally mounted in the container, and has alever that is depressed to lift a seat closure part. A plunger isslideably mounted on the container and slides within a cup arrangementthat extends to a lower portion of the container to avoid the escape ofair or sewer gas. The container has a slot that allows the refill of thecup arrangement with water at each tank refilling, to keep the cuparrangement filled with water to assure a sewer gas seal therein.

The novel features of the invention are set forth with particularity inthe appended claims. The invention will be best understood from thefollowing description when read in conjunction with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial sectional isometric view of a vacuum assist toiletconstructed in accordance with the present invention.

FIG. 2 is an exploded isometric view of the container assembly of thetoilet of FIG. 1.

FIG. 3 is a plan view of the lower portion of the container assembly ofFIG. 2.

FIG. 4 is a side sectional view of the container assembly of FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 illustrates a vacuum assist toilet 10, which includes aconventional toilet tank 12 with a tank bottom 14. Water held within thetank is used to flush waste in a toilet bowl 16. The toilet bowl has anoutlet 20 that forms an upper trap 22 and a lower reservoir 24, and apassageway 26 between them. An inlet valve 30 fills the tank to apredetermined high water level 32, with the water also filling acontainer 34 of a container assembly 36. When a flush valve 40 isoperated, water in the tank (primarily water within the container 34)flows out through the flush valve, and through a water tunnel 42 to thetoilet bowl 16 to "push" out material lying in the bowl. When the waterlevel in the container 34 falls, it creates a vacuum in the upperportion of the container. A vacuum conduit 44 leads from the upperportion of the container to the passageway 26 of the toilet bowl outlet,to apply a vacuum thereto that "draws" out the contents of the toiletbowl. The addition of the vacuum to "draw" out the contents during aflushing, enables a given amount of water, such as 1.6 gallons, toachieve a better flushing in a vacuum assist toilet than is normallyachieved by only directing water into the toilet bowl.

The volume within the toilet tank 12 may be considered to be dividedbetween the contained volume within the container 34, and an uncontainedregion or volume 50 that lies within the tank but outside of thecontainer 34. Previously, applicant not only placed the inlet valve 30in the uncontained volume 50, but also placed the flush valve In theuncontained volume. A conduit near the bottom of the container was usedto pass water into the container when the tank was refilled, and to passwater from the container into the uncontained volume and through theflush valve during a flushing. Applicant found that a tall tank wasrequired for a flushing of given effectiveness (a predetermined numberof light and heavy balls in the toilet bowl are flushed). The high tankallowed water with a large head (large pressure) to flow from the tankarea around the container rapidly down through the outlet valve, whilealso causing a moderately rapid outflow of water from the container toproduce a vacuum therein. A toilet tank of lower height is generallydesirable, and applicant has changed the design of his vacuum assisttoilet to achieve this.

In accordance with one aspect of the invention, applicant now places theflush valve 40 within the container 34, rather than in the uncontainedvolume 50 lying within the tank but outside of the container. This hastwo advantages. A first advantage is that there is little obstruction tothe rapid outflow of water from the container through the flush valve 40into the water tunnel 42, for most of the water. The virtuallyunrestricted outflow of water from the container through the flush valve40 results in a very rapid outflow of water, that would otherwiserequire a taller container and taller tank. A second advantage is thatalmost all water used in a flushing flows out from the container 34,where the vacuum is generated that is applied to the trapway 26 of thetoilet bowl outlet. As a result, a vacuum of larger negative pressureand volume is created for application to the passageway 26 to betterdraw out the contents of the toilet bowl.

For the present application, applicant prefers to place the inlet valve30 in the uncontained volume 50 lying outside of the container 34. Thisallows a conventional toilet inlet valve 30 to be used in a simplemanner. A water conduit 60 flows water from the uncontained volume 50into the container 34 to refill it after each flushing.

FIG. 1 shows the front wall 62 of the container, with the conduit 60lying at the rear wall 64. FIG. 2 shows the rear wall 64 of thecontainer, to better show the conduit 60. The high water level 32 in thetank, lies at about the top of the container 34. The water conduit 60has a top 66 that lies five-eighths inch (1.6 cm) below the top wall 70of the container. As a result, water in the uncontained volume outsidethe container, falls only about one-half inch during a flushing, to thelevel of the conduit top 66. After a flushing, when the inlet valveopens, almost all of the water entering the tank overflows the conduittop 66 and refills the container, with additional water being used tofill the container and the uncontained volume about one-half inch to thehigh water level 32.

It can be seen from FIG. 2, that the container 34 includes upper andlower container parts 72, 74. The lower container part forms a groove 76into which a tongue 80 of the upper part fits, the tongue 80 lying atthe bottom of the upper container part. This holds the container partstogether and allows them to be forcefully separated. The container has abottom wall 86, the front and rear walls 62, 64, and end walls 88. Thecontainer includes a neck 82 that projects up from the top wall 70, anda cap 84 that fits over the neck and forms an air tight seal thereat.The neck 82 is of large diameter, and the cap 84 can be removed toobserve, clean, and replace parts, especially the flush valve, withinthe container. The top of the vacuum conduit 44 extends into the neck 82to leave the top of the vacuum conduit about as high as possible.

The water conduit 60 includes a depending part 90 that is received in atrap 92. The water conduit has openings only at 94, 96 that lie deepwithin the trap 92. The trap 92 contains water at all times (during andbetween flushings), and assures that any sewer gas that enters thecontainer 34, will not escape into the uncontained volume of the tankand into the environment

FIG. 4 shows some details of the flush valve 40 and of the rest of thecontainer assembly. The container forms a seat opening 100 through whichwater is released to flow through the water tunnel to the toilet bowl,with the bottom wall also forming a valve seat 102. A flush valve member104 includes a float 106 and a yolk 110 that is pivotally mounted on apair of trunions about an axis 112. The trunions lie on brackets 114extending up from the bottom wall 86. A lever 116 can be depressed by aplunger 120 to pivot up the rest of the float valve member, including aseat closure part 122 that extends around the float 106. When the seatclosure part 122 has lifted a certain distance off the valve seat, thebuoyancy of the float 106 raises the valve member high above the valveseat, as in common practice. When the flush valve member has beenoperated, water in the large container chamber enclosure 131, which isinitially at the high water level 32, rapidly moves out through thevalve seat 102 and seat opening 100 towards the toilet bowl. There islittle restriction to the rapid outflow of water from the containerchamber 130, so the outflow is rapid. The outflow is, on average, asrapid as would previously require a much taller tank.

The lower half 124 of the container is isolated from the uncontainedvolume 50 lying around the container, so water cannot flow largelyhorizontally from the bottom portion (below level 125 which is half thehigh water level) of the uncontained volume into the container during aflushing. Substantial isolation (there is no passage with an openinggreater than one-fifth the area of the seat 102) also assures that atleast 75% of the flush water comes from water stored in the containerbetween flushings.

Applicant initially constructed the container assembly so there was nobarrier around the valve seat 102 and flush valve member 104. Applicantthen placed a barrier similar to the barrier 130, around the flush valvemember 104 and valve seat 102, to prevent the outflow of water lyingonly perhaps two inches above the valve seat 102. Such "last two inches"of water has only a small head, so it flows relatively slowly outthrough the valve seat 102 and does not help much in a flushing ascompared to its volume. Applicant found that when the barrier extendedcompletely around the flush valve member, that the flow was directeddownward along the flush member and closed it at the beginning of aflushing. To prevent this, applicant provides a barrier slot 132 in thebarrier 130, at a location near the seat closure part 122 of the flushvalve member, and preferably at a location opposite the pivot axis 112.The barrier slot 132 allows the rapid flow of some water through thevalve seat 102 without pushing down the raised flush valve member, sothe flush valve member does not close much too early.

FIG. 3 shows the center or axis 140 of the valve seat and seat closurepart 122, and shows that the barrier slot 132 extends by an angle A of60°. This leaves the tall barrier portion 134 to surround the valvemember by more than 200°, and actually about 300°. Applicant found thatthe angle A of 60° enables sufficient largely horizontal flow below theraised flush valve member, that the valve member does not close tooearly during a flushing. However, the valve member closes earlier thanwithout the baffle, with the particular container assembly closing with13/4 inch (4.5 cm) of water still lying in the container (above thesurface 166). It may be said that with the barrier (of at least 2 inchesheight), the barrier slot allows fine adjustment of the height at whichthe flush valve closes, to produce a 1.6 gallon (6 liter) flush. Asshown in FIG. 4, the barrier lies at a level 142 of 13/4 inch at theslot 132, to prevent excessive horizontal and slow flow into the valveseat The average height of the barrier is preferably at least one inchabove the sealed surface of the valve seat. As shown in FIG. 3, thevertical cross-section of the area within the barrier, as seen in avertical or plan view, is less than half the total cross-sectional areaof the container.

The plunger 120 has a top 150 which is depressed to lift the seatclosure part 122 of the flush valve member 104 off the valve seat andbegin a flushing. A spring 152 urges the plunger upwardly. A cuparrangement 154 includes a stationary guide 156 that is formed by thecontainer top wall and that surrounds the plunger. A cup 160 is fixed toa lower portion 162 of the plunger to move up and down with it. The cup160 serves to hold water, to prevent any sewer gas that flows backwardinto the container 34, from flowing into the uncontained region of thetank and into the environment. Such sewer gas could flow backwardthrough the vacuum conduit 44. As shown in FIG. 1, applicant provides aslot 164 in the top wall 70 and front wall 62, to allow water to refillthe cup arrangement 154 (FIG. 4) every time the tank is refilled. Thebottom of the slot 164 is at the same level as the top of conduit 60,which is slightly below the minimum water level in the filled tank.

Applicant has constructed a container assembly 34 of the constructionillustrated, with the container constructed to hold water of a highwater level 32 only 61/2 inches (16.5 cm) above the bottom surface 81 ofthe container (bottom surface 81 of FIG. 4 lies on the bottom 14 of thetank). The average height 165 of the container inside was about 6.8 inch(17.3 cm). The total height of the container was 73/4 inches (19.8 cm)between the bottom surface 81 and the top of the cap 84. An additionalthree inch height was required for the inlet valve and tank cover,resulting in a tank whose top was only eleven inches above the bottom 14of the tank and of the rim of the toilet bowl. The barrier 130 extended23/4 inches (7 cm) above the container bottom wall upper surface 166,except at slot 132 where the barrier height was 13/4 inch (4.5 cm). Thebarrier as shown in FIG. 3, had a length of 6.5 inches and width of 31/4inches, compared to the container length of 13 inches and width of 53/4inches. The top 168 of the container lower part 74 lay 1.8 inch (3.3 cm)above the upper surface 166 of the container bottom wall. The seat top102 lay about 0.5 cm above the container surface 166.

About 90% of the water used in each flushing came from water stored inthe container between flushings, with about 10% resulting from water inthe uncontained volume lying outside the container, flowing in throughthe water conduit near the beginning of a flushing (after water in thecontainer dropped a couple of inches).

In FIG. 2, the openings 94, 96 at the bottom of the water conduit 60were of a small size, having a combined open area of only about 0.4square inch (2.6 cm²), which is less than one-fifth the area of thevalve seat, which was of 21/8 inch diameter (area of 3.5 square inchesor 23 cm²). This assured that during the beginning of a flushing, waterflowed only slowly from the tank into the container, while water flowedrapidly out of the container, to assure that the level of water in thecontainer dropped rapidly near the beginning of a flushing to create avacuum to draw out the contents of the toilet bowl.

It is noted that FIG. 4 shows a pair of mounting bolts 170 that mountthe container rigidly in place in the tank. An additional pair ofbrackets, indicated at 172 can be formed on the top wall of thecontainer to hold a mechanism that depresses the plunger 120.

Thus, the invention provides an improved vacuum assist toilet, whichenables the very rapid outflow of water from within the tank towards thetoilet bowl, so that a tank of smaller height can be used and stillprovide a vigorous outflow of water for an efficient flushing. The valveseat through which water flows out of the tank, is formed at the bottomof a vacuum-generating container, so water can flow to the valve seatwith virtually no restriction, for very rapid outflow. The container issealed against the flow of water from the uncontained volume around thecontainer, into the container, at least in the bottom half of thecontainer. The container is stationary and the flush valve member ispreferably mounted within the container and pivotally mounted at thebottom of the container. The inlet valve can lie outside the container,and a water conduit is provided to refill the container, with the upperend of the water container lying only slightly below the high waterlevel.

Although particular embodiments of the invention have been described andillustrated herein, it is recognized that modifications and variationsmay readily occur to those skilled in the art, and consequently, it isintended that the claims be interpreted to cover such modifications andequivalents.

What is claimed is:
 1. A method for operating a vacuum assist toilethaving a toilet bowl with a toilet bowl outlet, a tank, a containerdisposed within said tank, and a vacuum conduit extending from an upperportion of the container to said toilet bowl outlet, so that a vacuum iscreated in an upper portion of the container and applied to the toiletbowl outlet as the water level within the container falls during aflushing of water into said toilet bowl, the method comprising the stepsof:during the flushing of water, directing the water from said containerinto the said toilet bowl without first passing said water out of saidcontainer through said tank; after the flushing of water, refilling saidtank through an inlet valve disposed in said tank but outside saidcontainer; during the refilling step, allowing said water to flow fromsaid tank into said container; wherein said step of flushing waterincludes isolating said container from said tank so that water at alevel below half the height of said tank is inhibited from flowing intosaid container.
 2. A method for operating a vacuum assist toilet havinga toilet bowl with a toilet bowl outlet, a tank, a container disposedwithin said tank, and a vacuum conduit extending from an upper portionof the container to said toilet bowl outlet, so that a vacuum is createdin an upper portion of the container and applied to the toilet bowloutlet as the water level within the container falls during a flushingof water into said toilet bowl, the method comprising the stepsof:during the flushing of water, directing the water from said containerinto the said toilet bowl without first passing said water out of saidcontainer through said tank; after the flushing of water, refilling saidtank through an inlet valve disposed in said tank but outside saidcontainer; during the refilling step, allowing said water to flow fromsaid tank into said container; forming said container with a bottom walland sidewalls which substantially isolate the interior of said containerfrom said tank at the lower half of said tank; establishing a seatopening in said bottom wall of said container and providing a valve seaton the seat opening; and establishing a flush valve member in saidcontainer.
 3. The method recited in claim 2, further comprising the stepof:during the directing, flowing water from said container down throughsaid seat opening to said toilet bowl during the flushing of water whileavoiding the passage of water from the bottom of said tank to said seatopening.
 4. The method recited in claim 2, further comprising the stepsof:during the flowing step, flowing said water through said flush-valveseat while said flush-valve member is raised above said flush-valveseat; establishing a barrier with a height not greater than 4centimeters at least 200° around said flush-valve seat and around atleast said lower portions of said flush valve; and during the flushingof water, directing most of the water into said barrier before directingthe water through said flush-valve seat.